Import `constants` module instead of importing constant values directly

[Wauplin]

Best described by @albertvillanova in huggingface/datasets#5196 (comment) and huggingface/datasets#5196 (comment).

Basically, change from

from huggingface_hub.constants import CONSTANT_VALUE

CONSTANT_VALUE
(...)

to

from huggingface_hub import constants

constants.CONSTANT_VALUE
(...)

everywhere.

⚠️ This will most probable brake some monkey-patching in downstream libraries. Let's be careful about how to perform such a change. E.g. let's do it and make some tests before merging.

[dankornas]

Hi, is this issue still available to work on? If yes, I would like to give it a shot. I have been eager to contribute to HuggingFace, and this would be a nice start.

[Wauplin]

Hi @dankornas, thanks for proposing to contribute on this one! It is open for contributions yes :) Maybe as a start you can work on a first PR that makes the change only in a few modules (instead of the entire codebase at once) so that we can iterate on it. What do you think? If you have any questions, please let me know!

Thanks in advance 🤗

[dankornas]

Hey @Wauplin, sounds good to me! Based on the comments that you provided in your first comment, I think I have a pretty good idea of what we want to do here. So, I will start playing around with this whenever I can and once I have something or if I have any questions, I'll be sure to get back to you :)

[Wauplin]

Good, sounds like we have a plan then :) Feel free to ping me whenever!

[WizKnight]

Hey @Wauplin , the task was completed to update constants in hf_api.py, can I work on other files as well or first wait for it to get reviewed and merged

[Wauplin]

I think it's best to definitively complete the first PR first, which should happen very soon!